No. As the study shows, Pornhub reported only so many accounts of child pornography being on their site, and they always try to shift the responsibility from themselves to the people who are uploading the content, when it's their site. They should require people to verify their age and verify who they are and that they're actually the people in the video before it can be uploaded, instead of just letting whatever be uploaded and then downloaded from their site, and then, oops, now that it's flagged as child pornography we're going to make people prove it's child pornography before we actually do something.
At the end of the day, they really don't want to remove the videos. In reality, their whole process should have been, from the beginning, having people verify their age and identity before the video can even be uploaded. So I don't think their promise is worth the paper at all.